Koichi Takase

Image-based control of skin melanin texture.

We introduce a useful tool for controlling the skin melanin texture of facial photographs. Controlling the skin melanin texture is an important task in the reproduction of posters, TV commercials, movies, and so on. We used component maps of melanin, which were obtained by a previous method [J. Opt. Soc. Am. A 16, 2169 (1999)] as the first processing step. We propose to control the melanin texture continuously and physiologically, based on the analysis of 123 skin textures in our database. The physiological validity for the change of the melanin texture is confirmed by comparing the synthesized image with an ultraviolet image, which can be used to predict the change of melanin texture due to aging. The control processes are implemented on programmable graphics hardware, and real-time processing is achieved for a facial videostream.

Image-based control of skin translucency

We propose a method for skin translucency control of facial images. This is one of the important tasks in the reproduction of posters, TV commercials, movies, and so on. As the first step of processing, we extract the component maps of melanin, hemoglobin, and shading from skin color images by using our conventional method. The extracted shading component is controlled to change the translucency of the skin by simple kernel operations for the component. The efficiency for the change of translucency is confirmed by using the images of numerical and optical skin phantoms. The method is also applied into the real skin color image with the consideration of each component, and realistic change of skin translucency was observed from the resultant images synthesized by the proposed method.

Real-time image-based control of skin melanin texture

In this paper, we present a novel process to control the skin melanin texture over a continuous range. The process is implemented on graphics hardware and can achieve real-time processing for a livevideo stream. A component map of melanin texture is utilized, which was extracted from a skin color image by our previous method [Tsumura et al. 2003]. A feature vector is calculated from the extracted melanin texture and shifted in a feature space to control the melanin texture over a continuous range. The feature space is constructed based on the texture database to extract physiologically plausible changes in the melanin texture.

Simulation of skin spectral reflectance based on an empirical model

We proposed a method to simulate the skin spectral reflectance based on an empirical model. The model was constructed based on the simulated data by Monte Carlo simulation of light transport in the skin model.

Computational lighting reproduction for facial live video with rigid facial motion

In the field of virtual studios in the television industry, the facial live video stream and background scenes must be composed in real time. One of the complex problems in this compositing is matching the lighting between the facial live video and the background scene. In this paper, we develop a practical lighting reproduction technique to reproduce the appearance of a face in the facial live video with rigid facial motion in real time under an arbitrary environmental lighting condition.

Super resolution based on texton substitution

The resolution of a texture image in computer graphics is determined by the camera system used to take the image. Zooming in on the object beyond the optical resolution results in a blurring of edges and details. This paper presents a “super resolution” method that uses a database of textures and texton substitution to create plausible high-frequency detail in enlarged texture images[Malik et al. 2001]. Conventional example based super-resolution techniques require the high computational cost and must be given the optimal parameters that depend on the input image[Freeman et al. 2000; Hertzmann et al. 2001]. In this paper, texton in the wavelet space and a pixel based (not a patch based) substitution is proposed for the practical use by their low computation process[Hopf et al. 2001].